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Knee Cap Pain (Patellofemoral Chondromalacia-PFC)

Early Softening (arthritis) of the cartilage behind the kneecap


Chondromalacia of the patella is usually caused by repetitive overuse and overloading of the kneecap.  It may be the result of trauma to the front of the kneecap such as falling on a hard surface or a dashboard injury.  Many PFC cases involve tracking problems of the kneecap.  These may be caused by congenital mal-alignment. Others are caused by severe muscle de-conditioning creating dynamic tracking problems. Chondromalacia is essentially early stage arthritis that is not seen on an X-ray.  It is a diagnosis made by history and exam.  It is graded in severity by direct visualization made during an arthroscopy.




Activity Modifications:


  • Sitting
    - Avoid sitting in low chairs.  Raise your seat at work and in your car.  Use a pillow on your car seat and move it back for more legroom.  Use an aisle seat on a plane, at a movie, etc.  Consider elevating your work/computer workstation using a barstool-like chair with arms and an elevated desk.  Change the position of your knees frequently, every 15-20 minutes.  Consider speaking on the phone from a standing position to allow more changes of the knee position.
  • Lifting
    – Avoid lifting with your knees bent. Avoid lifting objects up stairs. Consider leaving collected items at the bottom of the stairs and have someone else bring them up the stairs for you. Bring groceries in and set them on the counter not the floor.  Ask other family members or friends to lift heavy items from the car.
  • Stairs
    - Avoid stairs unless when necessary. Walking down stairs creates contact pressures of five times body weight across the kneecap of the joint.  Reduce average number of trips up and down stairs by half.  Use the elevator at work.
  • Hiking/Walking
    - Walk on flat ground with well-cushioned shoes and arch supports or orthotics.  Use a trekking stick especially if you are hiking in the hills.  This is important for hiking downhill to decelerate and offload your kneecap.


Workout Exercises


The Safest Exercises:


  • Straight leg raises with 2-5 pound ankle weights
    . Performed by laying flat on a bed or mat. Tighten your thigh muscle (quadriceps), keep your knee perfectly straight and raise your leg for a twenty-second count. Alternate legs. Perform 15-20 times/day.
  • Stationery bike or cycling
    . This is very safe for this knee condition. Place your bike seat up high. Use low tension (levels 1-3 on a Lifecycle).
  • Short arc leg presses or wall slides
    . It is very easy to do these incorrectly and worsen your symptoms.
  • Lunges
  • Squats
  • Knee Extension Machines
  • Step Aerobics/Step Workouts
  • Running Bleachers
  • Ice- Ice your knee when it is swollen or if painful after activity.
  • Anti-inflammatory Medication
    – Advil (ibuprofen), Aleve (Naproxen) or prescription non steroidal anti-inflammatory medications (NSAIDS) can reduce swelling, inflammation, and pain.  Use before and/or after activity.  Use as prescribed.  Observe for stomach symptoms such as pain or burning.  Discontinue if you feel stomach symptoms.  If you require these medicines on a daily basis you should follow blood tests with your primary care doctor to check for kidney and occasionally liver problems.
  • Glucosamine/Chondroitin
    - These are naturally found lubricants in our joints.  They can be purchased over the counter and appear to provide a protective function to our joints.
  • Orthotics
    - These can support the arch of the foot and helps to improve the mechanical alignmentof the patellofemoral joint.
  • Braces
    - Patellofemoral braces can support the kneecap.  Both static and dynamic patellofemoral stabilizing braces are available.
  • Weight loss
    - Losing weight can significantly decrease the contact forces across the patellofemoral joint.
  • Cortisone injections
    - These are used occasionally to reduce inflammation if other treatments have failed.


For the leg press machine, only bend your knees 10-20 degrees.

For wall slides, only slide one inch down the wall (again this should place your knee into only 10-20 degrees of flexion) and hold for a 20-30 second count. Use 10-20 pound hand weights with your arms by your side. Alternate, right, and left sides. Perform 15-20 repetitions on each side. If this exercise causes pain, you are usually sliding too low on the wall.


The Worst Exercises:


These will aggravate your knee pain:

The common theme here is to avoid loading the knee when it is bent 30 degrees or more.  This is the position that creates increased contact pressure behind the kneecap and subsequently wearing of the cartilage.

For cardiopulmonary conditioning, these machines/exercises are listed from safest to most unsafe for your knees.

> Stationery bike, cycling, swimming

      > Elliptical machine

            > Treadmill, walking (no incline)

                  > Stairmaster

                        > Treadmill, incline

Physical Therapy


Physical therapy can be very effective in strengthening your leg muscles.  Common techniques include taping of the kneecap to improve alignment.  This allows more effective strength training of the quadriceps. Ice, ultrasound, and electrical stimulations are also used to strengthen the quadriceps muscle more directly.

Patellofemoral Joint Mal-alignment (Subluxation)

Many cases of kneecap pain are caused by congenital kneecap tracking problems.  This is a complex problem with a wide spectrum of involvement.  This causes the kneecap to track out of its normal groove causing uneven wear on the backside of the kneecap.  This is analogous to a poorly aligned tire on a car that causes the edge of the tire tread to wear more rapidly.

The pain associated with mal-alignment can be improved with all of the treatments mentioned above.  Proper muscle strengthening can improve the patellofemoral tracking.  Patella stabilizing braces and shoe orthotics can also improve the mechanical alignment of the kneecap.




Moderate to severe cases of chondromalacia of the patella with patellafemoral subluxation that do not improve with extensive conservative treatment and time may require surgical realignment of the kneecap.

Severe cases of chondromalacia of the patella without mal-alignment may also require surgery.  This can involve procedures that smooth the cartilage surface, operations that graft new cartilage cells onto the joint surface, and techniques that relieve pressure from behind the kneecap by cutting the upper tibia and elevating it forward.